Department of Internal Medicine, Cardiovascular and Immunological Sciences, University Federico II, Naples, Italy.
Eur J Nucl Med Mol Imaging. 2011 May;38(5):969-75. doi: 10.1007/s00259-010-1697-5. Epub 2010 Dec 21.
Functional characterization of atherosclerosis is a promising application of molecular imaging. Radionuclide-based techniques for molecular imaging in the large arteries (e.g. aorta and carotids), along with ultrasound and magnetic resonance imaging (MRI), have been studied both experimentally and in clinical studies. Technical factors including cardiac and respiratory motion, low spatial resolution and partial volume effects mean that noninvasive molecular imaging of atherosclerosis in the coronary arteries is not ready for prime time. Positron emission tomography imaging with fluorodeoxyglucose can measure vascular inflammation in the large arteries with high reproducibility, and signal change in response to anti-inflammatory therapy has been described. MRI has proven of value for quantifying carotid artery inflammation when iron oxide nanoparticles are used as a contrast agent. Macrophage accumulation of the iron particles allows regression of inflammation to be measured with drug therapy. Similarly, contrast-enhanced ultrasound imaging is also being evaluated for functional characterization of atherosclerotic plaques. For all of these techniques, however, large-scale clinical trials are mandatory to define the prognostic importance of the imaging signals in terms of risk of future vascular events.
动脉粥样硬化的功能特征是分子成像的一个很有前途的应用。放射性核素技术用于大动脉（如主动脉和颈动脉）的分子成像，以及超声和磁共振成像（MRI），已经在实验和临床研究中进行了研究。技术因素包括心脏和呼吸运动、低空间分辨率和部分容积效应，这意味着冠状动脉粥样硬化的非侵入性分子成像还没有准备好进入黄金时期。正电子发射断层扫描成像（PET）用氟脱氧葡萄糖可以高度重现性地测量大动脉的血管炎症，并且已经描述了针对抗炎治疗的信号变化。当使用氧化铁纳米颗粒作为造影剂时，MRI 已被证明可用于量化颈动脉炎症。铁颗粒的巨噬细胞积累允许用药物治疗来测量炎症的消退。同样，对比增强超声成像也正在被评估用于动脉粥样硬化斑块的功能特征。然而，对于所有这些技术，都需要进行大规模的临床试验来确定成像信号在未来血管事件风险方面的预后重要性。
